a. Field of the Invention
This invention relates to electrical signal amplifying system, and more particularly to an arrangement for stabilizing the operation characteristics of a direct-coupled transistor amplifier.
B. Description of the Prior Art
Through the use of the well known direct-coupling technique, a transistor amplifier may be constructed which eliminates the need for interstage blocking capacitors. The elimination of such coupling capacitors provides improved frequency response over a wide range. However, because of the direct-coupled circuit's ability to amplify direct-current as well as alternating-current signals, extreme care must be taken to stabilize the quiescent operating point for each transistor. Small variations in the operating point of the earlier stages may be amplified to cause profound changes in the latter stages.